WiFi (802.11XX) standards typically assume that a link is stationary and assume that the link budget, and therefore transmitted power, is stable over the length of a burst. Early WiFi systems used only short bursts (e.g., bursts around 200 microseconds) and low modulation complexity, so amplifier stability was not a problem. More recent WiFi standards, such as 802.11AC, allow for longer bursts (for improved throughput), and support 256QAM modulation which call for better amplifier linearity to achieve the specified EVM. Under this standard, excellent amplifier performance is be maintained over a long burst, but an amplifier's gain tends to drop as it warms up.